Matthew A. Baum

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Issue Bias: How Issue Coverage and Media Bias Affect Voter Perceptions of Elections

      It is virtually a truism in American politics that a focus on some issue areas during election campaigns, like national security or traditional values, redounds to the benefit of Republicans, while emphasis on other areas, like education or social security, benefits Democrats. Political scientists refer to this phenomenon as “issue ownership” (Petrocik 1996, Ansolabehere and Iyengar 1994). To the extent that one or the other party benefits disproportionately from media emphasis on particular issues during election campaigns, it is possible that, whether intended or not, media coverage may disproportionately benefit one or the other party. If so, this would appear to be an important potential form of bias.

       Baum and Gussin (2004) find that typical individuals use media outlet labels as a heuristic, to assess the validity of information presented by different outlets. Liberals tended to “find” a conservative bias in outlets they believed, ex ante, have a conservative slant, even if the content was actually from an outlet that they believed to have a liberal slant. The opposite was true for conservatives. We extend that research by investigating how issue ownership and the Hostile Media Outlet Phenomenon mediate, separately and in interaction, voter perceptions of media campaign coverage. We look at the effects of story selection on individuals’ perceptions concerning which party benefits more from media issue coverage. To do so, we conducted an experimental content analysis in which we asked subjects to code transcripts and articles, from eight major network and cable news broadcasts and newspapers, about the 2000 presidential campaign.

       We modified the transcripts and articles to create three distinct sets of treatment stimuli. One set correctly identified the source of the material. The second incorrectly identified the source and, in the third, all identifying elements were removed.  We investigate whether individuals with differing political preferences are more or less likely to view certain issues as favorable to one or the other party, as well as the extent to which their propensity to do so is mediated by media outlets’ “brand names,” independent of the true sources of news coverage. We find that, except when they have strong prior beliefs about the ideological orientation of a media outlet, our subjects rely far more on issue ownership as a heuristic than on the hostile media heuristic. However, when they do have strong prior beliefs regarding outlet ideology, the opposite pattern prevails, with subjects relying on the hostile media heuristic to evaluate news content.


You can download the current version of this paper, in pdf format, here.

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